In-Syringe Micro Solid-Phase Extraction Method for the Separation and Preconcentration of Parabens in Environmental Water Samples

Abstract

In this study, a simple, rapid and effective in-syringe micro-solid phase extraction (MSPE) method was developed for the separation and preconcetration of parabens (methyl, ethyl, propyl and butyl paraben) in environmental water samples. The parabens were determined and quantified using high performance liquid chromatography and a photo diode array detector (HPLC-PDA). Chitosan-coated activated carbon (CAC) was used as the sorbent in the in-syringe MSPE device. A response surface methodology based on central composite design was used for the optimization of factors (eluent solvent type, eluent volume, number of elution cycles, sample volume, sample pH) affecting the extraction efficiency of the preconcentration procedure. The adsorbent used displayed excellent absorption performance and the adsorption capacity ranged from 227–256 mg g−1. Under the optimal conditions the dynamic linear ranges for the parabens were between 0.04 and 380 µg L−1. The limits of detection and quantification ranged from 6–15 ng L−1 and 20–50 ng L−1, respectively. The intraday (repeatability) and interday (reproducibility) precisions expressed as relative standard deviations (%RSD) were below 5%. Furthermore, the in-syringe MSPE/HPLC procedure was validated using spiked wastewater and tap water samples and the recoveries ranged between from 96.7 to 107%. In conclusion, CAC based in-syringe MSPE method demonstrated great potential for preconcentration of parabens in complex environmental water.

Magnetic Fe3O4@Mg/Al-layered double hydroxide adsorbent for preconcentration of trace metals in water matrices

“…The values in the desirability profile (Fig. 8 ) that are closer to 1.0 imply that the corresponding parameter or variable condition is optimum 37 . The optimum conditions for simultaneous preconcentration of As(III), Cd(II), Cr(III), Co(II), Ni(II), and Pb(II) ions were selected to be 6.5, 84 mg, 10 min, and 2.0 mol L −1 for sample pH, mass of adsorbent, extraction time and eluent concentration, respectively.…”

Exploration of a Molecularly Imprinted Polymer (MIPs) as an Adsorbent for the Enrichment of Trenbolone in Water

“…The optimisation results were analysed using the analysis of variance (ANOVA), response surface methodology and desirability function in order to determine the significant factors, interaction effects and desirable conditions for optimum extraction [68]. The analysis of variance is reported in the form of a Pareto chart ( Figure 5), where the redline is indicative of the 95% confidence interval that a factor has significant effect on the extraction of trenbolone using the MIP [69].…”

Magnetic Mesoporous Carbon/β-Cyclodextrin–Chitosan Nanocomposite for Extraction and Preconcentration of Multi-Class Emerging Contaminant Residues in Environmental Samples

“…Until now, different kinds of adsorbents have been used for extraction and preconcentration of PPCPs. These include multi-walled carbon nanotubes [ 33 ], nanofibers [ 27 , 28 , 34 ], graphene oxide nanocomposites [ 19 , 35 ], biopolymer-based composites [ 36 , 37 ], activated carbon, metal–organic frameworks [ 2 , 38 ] and metal oxide nanocomposites [ 28 ]. Recently, our previous research prepared a biodegradable superabsorbent based on a magnetic mesoporous carbon/β-cyclodextrin–chitosan (MMPC/CycChit) nanocomposite for removal of fluoroquinolones (FQs) from environmental samples [ 39 ].…”

“…The method was based on dispersive magnetic solid-phase extraction (DMSPE) based on the previously reported MMPC/CycChit adsorbent combined with high-performance liquid chromatography with diode array detection (HPLC-DAD). The choice of analytes to be investigated was based on the previous studies which revealed that anticonvulsants, beta-blockers, parabens and fluoroquinolones (FQs) are frequently detected in South African water systems [ 7 , 31 , 36 , 44 , 45 ]. The experimental factors (mass of adsorbent, eluent type, eluent volume, extraction time, desorption time and sample pH) affecting the extraction and preconcentration procedure were optimized using univariate and multivariate approaches.…”